Questions tagged [signature]
This tag should be used for questions regarding digital signatures. A digital signature proves that the owner of a private key produced or endorsed a given message. These are used in transactions to prove that an output can be spent in a transaction.
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Is there a set length that a signature can be?
I'm reading this page which describes the following method of creating a stack:
OP_0 <A sig> <B sig> OP_2 <A pubkey> <B pubkey> <C pubkey> OP_3
Sig Stack Pubkey ...
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Validation of segwit v0-v1 tx automatically adds OP_CHECKSIG?
When I create a segwit transaction v0 (P2WPKH) or v1 (P2TR key-path spend) I do like that (let's spend a P2TR output):
Locking Script (of the P2TR output I'm spending): OP_1 PK_size PK
Witness: 1 (...
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Continuation question about nonce randomness and verification of the randomness by signing parties
Original: Can a signer recover their own signature's nonce `k`?
Note that under normal circumstances it is infeasible to randomly generate the same nonce, so either a non-random nonce has to have ...
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Can a signer recover their own signature's nonce `k`?
I am proofreading a blog post about nonce reuse. One point that comes up is whether someone could recover another person's private key if the other user reuses the same nonce. In that context, it was ...
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Error validating transaction: unexpected witness payload for non-witness script in a P2TR using script path
I am trying to create a raw transaction P2TR, spending a Taproot UTXO using the script path.
I did the following:
Create a random private key d and corresponding pubkey P (the internal pubkey)
...
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non-mandatory-script-verify-flag (Invalid Schnorr signature) when I try to send a P2TR tx on testnet
I'm learning to create tx from scratch in order to understand better how bitcoin tx works and how they are structured. I learnt to create tx with legacy address, segwit v0 and I am now learning ...
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Bitcoin Core file with the signing keys was removed from repo. How is the process supposed to be now?
Yesterday this PR was merged into the Bitcoin repository, and the process described at https://bitcoincore.org/download mentions that to validate the source code, you must download the txt file with ...
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Is Curve25519 better option than Secp256k1?
Are signatures over Curve25519 better than over Secp256k1 or are there major drawbacks?
How do, for instance, EdDSA/Schnorr using Curve25519 compare with ECDSA/Schnorr for Secp256k1?
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Signing taproot key-path transaction from rust-bitcoin
I'm trying to make a taproot HTLC using rust-bitcoin for an atomic swap protocol. My plan is that in the "happy case" of my protocol, the coins are spent with the key-path, and then there is ...
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Anti-exfil protocol can't be verified on multiple hardware wallets
Regarding the nonce side channel attacks detailed in posts like this one by Blockstream. Which references this mailing list by Pieter Wuille. The idea is to add another layer of protection against a ...
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LN-Channel: Do I have to use new private keys for each HTLCs out of security?
I have a question regarding the security of HTLCs in a LN-channel.
In a LN-transaction with multiple HTLCs (routings) to the destination one is using the signature of each node provider so that the ...
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BLS signatures vs Schnorr
How do BLS signatures (or other pairing-based schemes) compare to Schnorr signatures in terms of cryptographic assumptions?
Is it faster to verify, say 100 (non-interactively) aggregated BLS ...
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Getting a high s value rejection although s < N/2
Using the mempool app on my full node from mynode, when transmitting a raw tx with more than one output I get:
non-mandatory-script-verify-flag (Non-canonical signature: S value is unnecessarily high)....
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How many digital signatures appear in a block?
I am wondering how many times ECDSA digital signature are used across transactions in one block.
Let's take for example Block #735,273. It contains 405 transactions. My understanding is that each ...
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Question regarding the Z value of bitcoin Transaction
Is there such a value as a negative Z or inverse Z related to the original Z value, which is the double SHA256 of the unsigned tx+01000000. I know there is a negative S value, is there a negative Z as ...
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Were uncompressed public keys always supported by Bitcoin?
I was wondering when compressed public keys were introduced to bitcoin, then I saw this quote from this answer:
The original Bitcoin software didn't use compressed keys only because their use was ...
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What are Known Bits in a bitcoin Transaction?
How do I know if my signatures has leak/weak signatures?
Is there a website or script where I can input my signatures to check for weak/leak Nonce part?
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Exploiting the use of signature?
I've just learned signatures and why they're used in blockchain.
As I understand there is a key pair that consist of one public key and one private key:
Private keys are used to sign a message(...
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Can someone calculate my private key if I send the same amount to one address?
If I send the exact same amount to the same address in two separate transactions, can someone calculate my private key from the scriptSig? Will the signature (S) and the message (Z) be same?
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Is any 256-bit combination a Bitcoin private key?
I've recently been implementing a simple Bitcoin wallet and some libraries seem to disagree with address derivation from the same WIF private key, and thus wouldn't sign transactions. After that, I ...
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Is there software that can scan for reused R-values?
Is there any up-to-date program that can check for reused R-value for a specific Bitcoin address? (I don't want to scan the whole blockchain, just for a particular address.)
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Why we need to repalce the ScriptSig with the previous ScriptPubKey when calculate the per input signature hash?
I'm reading Programming Bitcoin. And in Chapter7, the author talked about the way how signature hash is calculated by replacing the transaction's ScriptSig with the corresponding previous ScriptPubKey....
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How and when were high-s signatures made non-standard?
I was just trying to pin-point which BIP made high-s signatures non-standard. BIP62 proposed it as a new consensus rule, but was withdrawn. I couldn't find it in another BIP.
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btc transaction by Digital signature
I have old btc wallet and I have Digital signature but i don't have Private key , Is there any way for withdraw btc from wallet just by Digital signature ?
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Can The Redeem Script Consist Of Only 1 Public Key In P2SH Transactions:
I have a few questions relating to Bitcoin Signatures And P2SH:
Why is P2SH used as opposed to other forms? Is it still prevalent today - has SegWit made it redundant or less useful, if not, what is ...
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Where Is Signature Data Stored In Post-SegWit Transactions?
If i'm correct, i am pretty sure that signature data such as the scriptsigsize
and scriptsig is stored outside the Tx_Data of a Bitcoin transaction. But then where is it stored? Is it in the block or ...
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How is a Bitcoin transaction signed using ECDSA?
I am quite familiar with the way secp256k1 ECDSA works as well as the equations that are utilised. However, I have no idea how this ECDSA applies to signing Bitcoin (SegWit Format) and transferring it ...
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SegWit signing algorithm and its improvement
I was reading about Segregated Witness upgrade from the book Mastering Bitcoin by Andreas and there were some questions I have not figured out. I am appreciated to get some of your help!
A) There was ...
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Can the difference be determined between two nonces k1, k2, having a linear relationship if the nonce and private key are unknown, i.e., k2 - k1 = n?
My question is related to weak signature vulnerability testing where a hypothetical attacker does not know the values of the nonce or private key itself, but can determine that the nonce 'k1' is ...
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Segwit includes the input amount in the SignatureHash. What possible attack can this prevent?
Legacy transactions only include transaction components in the SignatureHash, but segwit transactions also add the amounts of inputs in the SignatureHash.
Quoting from the Mastering Bitcoin Book:
...
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What is maxsigcachesize?
-maxsigcachesize= Limit sum of signature cache and script execution cache sizes to
What is this?
What is a sigcache?
What happens if it is set low and Can it have a bad effect?
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What is the script signature and PUSHDATA operation? [duplicate]
In bitcoin transactions, there is a part of the transaction known as the scriptSig. What does this mean? Also, what is the scriptSig (PUSHDATA opcode) operation.
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How to calculate the public key, compute point P and create signature using ECDSA?
I'm quite new to the intricacies of bitcoin cryptography and ECDSA and elliptic curve cryptography has me quite stymied. I am faced with a curve with the equation: y^2 = x^3 + 7 of order N=39 with ...
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Cryptographic digital signatures
I have a doubt since the public keys are known to everyone, so someone could falsify a transaction by writing down a deposit from a public address to another public address in a new block and solving ...
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Order of Signatures in Multisig-Scheme
3 Entities (A/B/C) create a collaborative Multisig Wallet (e.g. 2-of-3).
A creates an unsigned TX and shares it with B/C. They (B/C) sign and broadcast.
Looking at the TX on the network, can A make ...
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Standard library for schnorr signature algorithm
I am trying to create a blockchain demonstration to get used to the technology. The thing is: I want to use Schnorr signatures, but I can't seem to find a library for that, and I want to make sure ...
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Does signing a message as specified in AOPP incur a fee?
Does signing a message as specified in Address Ownership Proof Protocol (AOPP) incur a fee? I think not - there is nothing written in the specification about broadcasting
anything to the Bitcoin ...
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Is it Possible to Create Signature Chains for Private Keys to Sign Transactions with? Similar to how Certificate Authorities Use Intermediate Certs?
I am wondering if it is possible to implement this flow with bitcoin private keys, similar to how certificate authorities have a root cert and an intermediate cert used to sign csr's. It would be ...
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Bitcoin transaction inquiry
if suppose a someone offers a prize for anyone that can solve a specific challenge, how will the solver make sure that he/she collects the reward? Does the solver need to send the solution directly to ...
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What is the probability of an ECDSA signature being less than 71 bytes
Since DER requires R and s values being minimally encoded signed integers, they could be less than the expected 32 bytes. What is the probability that one or both of R and s are less than 32 bytes for ...
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Why can't I modify someone else's transactions, if I have their signature data?
As I know, signature system is adding signature to end of transaction. And doesn’t hash transaction, so others can know my signature.
If I can send a message directly to the node, can I use other’s ...
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What is the relationship between r in signature and the public key
I've been reading about ECDSA in here.
Step 11 says that
you only need the ‘x‘ value (20 bytes) for the signature, and that value will be called ‘R‘
Does that say that R is the x-coordinate of the ...
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How long is SIGHASH?
I am reading these two posts 1 2, and following step by step.
I almost understand, but I still have some questions.
Before signing, input script should be removed and replaced by pre locking script. ...
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How many times and where exactly is ECDSA used in Bitcoin?
I'm currently a little confused about where exactly ECDSA is used in the transaction process... some resources seem to say it's used once, whereas others seem to say it's used three times.
Which is ...
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How to calculate R, S, and Z from raw bitcoin transaction with witness?
How can I calculate the R, S, and Z values from a raw bitcoin transaction? I can extract them with rscan.py, but that doesn't work for new transactions.
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What is signature grinding?
What is signature grinding and why does the answer to What is the size and weight of a wrapped segwit single-sig input? "highly recommend it"?
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How to forge a signature with fixed Z value
I want to forge a signature with a fixed z value, what is the formula to do that
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What is an adaptor signature?
What is an adaptor signature in Bitcoin? A simple definition with some examples that could be understood without knowing cryptography in detail
user103136
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Curious about the Math that makes Bitcoin/Blockchain work ! Any good resources to learn it?
A bit of a background about me ; Computer Engineer but during my studies i didn't dive too deep into the maths , especially the maths that makes the blockchain and cryptography work
looking for advice ...
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Meaning of "Drop the signature" comments in OP_CHECKSIG code (Bitcoin v0.1.0)
I'm doing my homework by reading the C++ code of the 0.1.0 release of Bitcoin available here. I'm interested in better understanding how to validate transaction 1 of block 170. This transaction has ...
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